Antenna for mobile communications

ABSTRACT

An antenna is provided for mobile communications. The antenna comprises first, and second bodies of a conductor, each having races whose length and diameter are designed in consideration of the antenna&#39;s frequency and gain characteristics; a spacer of a non-conductor interposed between the first and second bodies so as to keep a given space between the respective races of the first and second bodies according to the frequency and gain characteristics; an inner core fixing two bodies to each other with screwed parts respectively inserted into screwed grooves each passing through the races&#39; bottom, and electrically connecting the first body to the second body; and a coupling part for feeder connection of a transmitting/receiving circuit for a mobile communications terminal.

TECHNICAL FIELD

The present invention relates to an antenna for mobile communications.More particularly, it relates to an antenna for mobile communicationsthat has an outer length significantly reduced in comparison to aconventional antenna's, and assures greatly improved performance.

BACKGROUND ART

In recent years, mobile communications equipments have spread far andwide. They became small in size gradually, and much effort has been madeinto the development of the quality of communication service. There arevarious mobile communications equipments, and particularly, there areterminals for mobile communications using code-division multiple access(CDMA), time-division multiple access (TDMA), or frequency-divisionmultiple access (FDMA), and iridium terminals using a communicationssatellite. In these terminals, their antennas are very important partsfor keeping good quality of communication service.

Such an antenna should basically have a voltage standing wave ratio(VSWR) of about 1.0, a high gain, a low radio-frequency resistance(RFR), a high emissivity, and a low reflection factor. It isadvantageous that the antenna is long in order to increase the gain.When it is too long, its RFR becomes high, and its gain is significantlyreduced. Besides, the long antenna gives a user inconvenience.

The antenna used for the conventional terminal for mobile communicationsis one using a loading coil. Because of the relation of the antenna'slength and gain, there is a limit to the antenna's length, and if theantenna is mounted within the terminal body, its performance becomesdeteriorated to lower the quality of communication service. Hence, theantenna is not embedded in the terminal but protrudes to the outside.Recently, the mobile communications terminal becomes small and light,but its antenna cannot be decreased in size. The protruding antenna maybe easily broken or damaged, and when a user carries the terminal in hisor her pocket, its antenna that may be caught causes inconvenience tothe user for putting it into the pocket or drawing it therefrom.

In addition, since the projecting antenna comes to be near the user'shead during use, the electromagnetic waves that are produced therefromare deleterious to the human body, and when it contacts the human body,the terminal's characteristics can be changed to cause noise or cut-offin the middle of telephone communication.

If a cellular phone is installed on an automotive vehicle, an antennafor vehicle cellular phone is provided. However, in the conventionalantenna for vehicle cellular phone, its position, direction and lengthare just controlled in order to enhance the quality of communicationservice, and this conventional technique could not fundamentally improvethe quality of communication service.

The problems of the conventional antenna will be now described referringto FIG. 1.

As depicted in FIG. 1, the conventional antenna is installed on eitherthe front side of an automotive vehicle or the window of its rear sideand then connected to a coaxial cable provided to the vehicle'sinterior. The conventional antenna is of on-glass type, and this type isa coupling one, and its radio-frequency interference (RFI) is abruptlydecreased during real use to deteriorate the quality of communicationservice and easily cut off the telephone conversation. In addition, thisantenna becomes about 53 cm in length when spreading its coil part. Whenthe antenna becomes long like this, the VSWR can be easily controlledbut the RFR is increased to lower the quality of communication service.The conventional antenna's gain is about 0 to 0.4 dBi, and the VSWR is1.4 to 1.5. Another conventional antenna has low productivity and is ofcomplicated structure.

DISCLOSURE OF THE INVENTION

Accordingly, the present invention is directed to an antenna for mobilecommunications that substantially obviates one or more of the problemsdue to limitations and disadvantages of the related art.

A first object of the present invention is to provide an antenna of newstructure which assures high gain characteristics and improved voltagestanding wave ratio (VSWR) with short length, thus enhancing the qualityof communication service.

A second object of the present invention is to provide an antenna thatis installed within a case of a cellular phone.

A third object of the present invention is to provide an antenna that isused to be mounted on an automotive vehicle or vessel.

Additional features and advantages of the invention will be set forth inthe description which follows, and in part will be apparent from thedescription, or may be learned by practice of the invention. Theobjectives and other advantages of the invention will be realized andattained by the structure particularly pointed out in the writtendescription and claims hereof as well as the appended drawings.

To achieve these and other advantages and in accordance with the purposeof the present invention, as embodied and broadly described, the presentinvention provides an antenna for mobile communications including firstand second bodies of conductor, each having races whose length anddiameter are designed in consideration of the antenna's frequency andgain characteristics; a spacer of a non-conductor interposed between thefirst and second bodies so as to keep a given space between therespective races of the first and second bodies according to thefrequency and gain characteristics; an inner core fixing two bodies toeach other with screwed parts respectively inserted into screwed grooveseach passing through the races' bottom, and electrically connecting thefirst body to the second body; and a coupling part for feeder connectionof a transmitting/receiving circuit for a mobile communicationsterminal.

The inventive antenna can be embedded in a cellular phone terminal tosolve inconvenience that occurs by conventional protruding antennas forcellular phone terminal.

An antenna anode region is formed with this inventive antenna installedwithin the terminal's case and the coupling part for feeding to onebody, and an antenna anode is formed by a shield plate of the cellularphone.

In addition, two antennas of basic structure are installed in the caseand one of the antennas serves as a feeder while the other one is ananode region.

In installing the antenna within the terminal, the antenna is disposedoutside of the shield plate in a certain direction. When forming thecathode region in the same structure as the anode region's, two regionscan be arranged in the same direction, and the anode region may make aright angle to the cathode region. In addition, each of the antennacoupling part and the antenna connector has a pin hole, and they may beconnected to each other by using a pin or via bolt-nut.

The inventive antenna's gain is higher than conventional ones, therebyenhancing the performance. Since the antenna for a cellular phoneterminal is installed in the terminal's case, this terminal can bevariously designed, and obviates any inconvenience that may occur by theprojecting antenna.

According to another aspect of the present invention, an antennaincludes an antenna base having a through hole into which an antennacable for communications equipment is inserted, and a plurality of screwholes formed on its bottom to mate with fixing brackets; a connectorhaving a bolt portion joined to the through hole's upper section, and aconnector pin protruding to the bolt portion's upper and lower parts, apart of the bolt portion being screwed to the through hole of theantenna base, and the antenna cable, inserted into the antenna base,being electrically connected to the connector pin protruding to thelower part; a holder of an insulating material, screwed to the boltportion of the connector protruding to the upper part of the antennabase, and precisely controlling a minute space between the boltportion's upper section and an antenna body for regulating the antenna'scapacitance; a first body having a bolt portion protruding from itslower portion and joined to the holder, the bolt portion having a pinhole into which a connector pin projecting to the connector's upper partis inserted for electrical connection, and a race of a given depthdesigned according to the antenna's transmitting/receiving frequency andgain, the race having screwed grooves on its bottom; an inner corehaving one end screwed to the screwed grooves, and spaced a givendistance away from the inner surface of the first body's race; a holderof cylindrical shape having a through hole through which the inner corepasses, and formed of an insulating material keeping a space of thefirst and second bodies, designed according to the antenna'stransmitting/receiving frequency and gain; and a second body having arace corresponding to the first body's, screwed grooves formed on itsinner upper section, for receiving the inner core, and a cap formed onits outer upper section.

Each of the fixing brackets includes a fixing disk, corresponding to thebottom of the antenna base, having a plurality of screw holes to whichscrews are fastened, a cable guide hole formed to receive the antennacable, and a coupling part formed on one side of the fixing disk to becurved by a given angle (e.g. right angle) and divided into two by anopen slit connected to the guide hole in such a manner that the firstand second fixing brackets, elastic pieces with compressed elastic forcebeing attached to the coupling part of the first fixing bracket, and thesecond fixing bracket's coupling part having a coupling slot into whichthe elastic pieces of the first fixing bracket are fitted, so that thebrackets may be either fixedly inserted into a gap of a car's interiorinto which the fixing disk can be fitted, or fixedly installed inside oroutside of the car by using screws.

It is to be understood that both the foregoing general description andthe following detailed description area exemplary and explanatory andare intended to provide further explanation of the invention as claimed.

BRIEF DESCRIPTION OF DRAWINGS

The accompanying drawings, which are included to provide a furtherunderstanding of the invention and are incorporated in and constitute apart of this specification, illustrate embodiments of the invention andtogether with the description serve to explain the principles of thedrawings:

In the drawings:

FIG. 1 depicts a conventional on-glass antenna mounted on an automotivevehicle;

FIG. 2A is an exploded sectional view of an antenna in accordance withthe present invention;

FIG. 2B is a sectional view of the assembled antenna in accordance withthe present invention;

FIGS. 3A and 3B depict the coupling structure of the inventive antenna,FIG. 3A shows the coupling structure using a screw, and FIG. 3Billustrates the pin-coupling structure;

FIGS. 4A to 4E depict the position of installation of the inventiveantenna;

FIGS. 5A and 5B show an antenna installed in a cellular phone inaccordance with another preferred embodiment of the present invention;

FIG. 6 is a perspective view of an antenna in accordance with a secondpreferred embodiment of the present invention;

FIG. 7 is a sectional view of the interior of FIG. 6's antenna;

FIG. 8 is an exploded sectional view of FIG. 1; and

FIG. 9 is an exploded perspective view of antenna fixing brackets inaccordance with the present invention.

BEST MODE FOR CARRYING OUT THE INVENTION

Reference will now be made in detail to the preferred embodiments of thepresent invention, examples of which are illustrated in the accompanyingdrawings.

FIGS. 2A and 2B depict the structure of an antenna in accordance withthe present invention. Specifically, FIG. 2A is an exploded sectionalview of an antenna in accordance with the present invention, and FIG. 2Bis a sectional view of the assembled antenna in accordance with thepresent invention.

As shown in the drawings, the inventive antenna includes first andsecond bodies 10 and 20 each having races 11 and 21 whose length anddiameter are fixed in consideration of the antenna's frequency and gain;a spacer 30 of non-conductor interposed between first and second bodies10 and 20 to keep a given interval between races 11 and 21; and an innercore 40 with screwed parts 41 and 42, each formed on its both tips andfixedly coupled to respective screwed grooves 12 and 22 of races 11 and21, thus fixing bodies 10 and 20 and electrically connecting first body10 to second body 20.

In case where such an antenna is installed within a cellular phone'scase, a coupling part has a bolt portion 50 formed on first body 10'sprotruding lower end, as shown in FIG. 3A, and an antenna connector 60,a female screw, receiving bolt portion 50. This antenna connector 60 isconnected to an antenna feeder of a transmitting/receiving circuit.

According to another feeder, as shown in FIG. 3B, each of inner core 40and antenna connector 60 has a pin hole, and antenna connector 60's pinhole is connected to that of inner core 40, coupled to first body 10,via a pin 710 for feeding.

A common-type cellular phone terminal's circuit board is surrounded by ashield partition not to be adversely affected by external radio waves,and the inventive antenna is also installed outside of the shieldpartition.

Since two bodies of this antenna are electrically connected to eachother through an inner core, the length of its surface is longer thanits outer length. With this antenna having the shorter outer length, adesired gain and characteristics can be obtained. Thus, the inventiveantenna can assure the more improved performance than a conventionalloading coil-type antenna's just by installing the antenna within a caseof a cellular phone terminal.

FIGS. 4A to 4F depict the position of installation of the inventiveantenna. Referring to FIGS. 4A and 4B, a shield plate 4 for a circuitboard is used as a cathode region, and an anode antenna 80 is installedoutside of shield plate 4. This anode antenna 80 may be provided to oneside or upper portion of the shield plate 4, as shown in FIGS. 4A and4B. That is, anode antenna 80 may be mounted on the left, right, upperor lower portion.

FIGS. 4C and 4D depict a cathode region designed to be similar to theanode region. As shown in FIG. 4C, two antennas 80 and 90 may be mountedon the same side as anode and cathode regions, or as shown in FIG. 4D,the anode and cathode regions can be each mounted vertically orhorizontally.

FIG. 4E shows a cathode region formed as a separate conducive pattern.As depicted in the drawing, anode antenna 80 can be mounted on one side,while the cathode conductive pattern is formed along the outside ofshield plate 4.

As described above, the antenna may he mounted on one or the other side,or upper or lower portion of the cellular phone terminal, and andaccording to the cathode region's structure, the anode and cathoderegions may be on the same or different position. The position of theinventive antenna is fixed in consideration of the size of the antennaor design of the cellular phone terminal.

FIGS. 5A and 5B depict another structure of antenna installation inaccordance with the present invention. As shown in the drawings, acircuit board surrounded by a shield plate is mounted in a front case 1of a cellular phone terminal, and protruding antenna connector 60 areprovided to a rear case 2. An antenna connector guide 61 for couplingantenna 80 to this connector 60 and fixing it is also provided to rearcase 2, and a guide 62 is formed to make a battery case be in accordwith the antenna coupling condition so that a battery 3 is joined torear case 2 while antenna 80 is being coupled to rear case 2. That is,in the inventive antenna 80, guides 61 and 62 are formed in the portionwhere battery 3 is mounted, and antenna connector 60 is installed andbattery 3 is then joined to rear case 2, whereby antenna 80 is notexposed to the outside. This antenna is designed not to be shielded by ametal.

The inventive antenna is installed outside of shield plate 4 and mountedwithin the celIular phone terminal case by joining first body 10 toantenna connector 60 electrically connected to the circuit board'stransmitting/receiving circuit. This folding antenna is 20 to 65 mm inouter length and 3 to 6 mm in diameter, which assures a desired gain.Thus, this antenna can be easily installed on any position of the caseand does not affect adversely the size design for being mounted withinthe terminal.

Mounting the inventive antenna in the cellular phone terminal's casedoes not increase the terminal's size, and the present invention canassure more improved performance than the loading coil antenna's.

As another preferred embodiment of the present invention, the inventiveantenna can be used for a mobile communications terminal for automotivevehicle. In this preferred embodiment an antenna employed for anautomotive vehicle is described by way of example, and the presentinvention may be used for a vessel's antenna, TRS equipment, an antennafor general communications, R.T.V. wireless equipment, a bar antenna, aradiotelephonic antenna.

FIG. 6 is a perspective view of an antenna in accordance with a secondpreferred embodiment of the present invention, and FIG. 7 is a sectionalview of the interior of FIG. 6's antenna. FIG. 8 is an explodedsectional view of FIG. 1.

The antenna of this preferred embodiment includes an antenna base 100serving as the antenna's cathode region; a connector 110 for connectingall antenna cable to an antenna body; a holder 120 keeping a spacebetween the antenna's cathode region (base) and anode region (body) andminutely controlling the space, first and second bodies 130 and 160;first and second bodies 130 and 160 each having a groove; an inner core140 inserted into first body 130's groove to connect first body 130 withsecond body 160; and a spacer 150 for keeping space between first andsecond bodies 130 and 160 and minutely controlling the space.

This antenna base 100 is of conical shape and has a through hole 102with screw threads and passing upper and lower portions of base 100, anda plurality of screw races 101 on its bottom to be electricallyconnected to each other through a fixing bracket, thus serving as acathode of the antenna.

Connector 110 includes a non-conductive bolt portion 112 screwed tothrough hole 102 of antenna base 100, and connector pins 111 and 113each protruding to the upper and lower parts of bolt portion 112 andacting as a feeder.

In this connector 110 bolt portion 112 is screwed to the upper part ofthrough hole 102 of antenna base 100 so that a part of it protrudes tothe upper part, and an antenna cable (not shown) is electricallyconnected to connector pin 111 within through hole 102 of base 100. Thisholder 120 is a cylindrical nut holder with a diameter that is the sameas base 100's upper diameter, and formed of an insulating materialscrewed to bolt portion 112 of connector 110 and a bolt portion 131formed on the lower portion of first body 130.

This first body 130 has bolt portion 131 joined to holder 120 on itslower section, and a pin hole 132 is provided to bolt portion 131.Connector pin 113 is fitted into pin hole 132 for electrical connection.

A race 134 of a given depth is designed according to the antenna'stransmitting/receiving frequency, and a coupling groove 133 to whichinner core 140 is screwed is formed on the bottom of race 134. Eachscrew thread 141 is formed on both ends of inner core 140, and innercore 140's one end is screwed to coupling groove 133 of first body 130.Inner core 140is spaced a given distance away from race 134 of firstbody 130.

Spacer 150 with a through hole into which inner core 140 is fitted isformed of an insulating material for keeping a space between first andsecond bodies 130 and 160. Second body 160 has a race 161 of a givendepth designed to the antenna's transmitting/receiving frequency, and acoupling groove 162 is formed on the upper section of race 161 andreceives inner core 140. Inner core 140, screwed to coupling groove 162,comes in close contact with first body 130's upper part with spacer 150therebetween.

The following description is about the steps in the assembly of thepresent invention.

Bolt portion 112 of connector 110 is screwed to antenna base 100'sthrough hole 102 so that a part of bolt portion 112 protrudes to base100's upper section, and holder 120 is screwed to bolt portion 112 ofconnector 110, projecting to base 100's upper section. Bolt portion 131is screwed to holder 120, simultaneously with inserting a connector pin113 of connector 110 into pin hole 132 of first body 130's bolt portion131. Inner core 140 is screwed through race 134 from the upper part offirst, body 130. Spacer 150 is fitted into inner core 140, and the uppersection of inner core 140 is screwed to coupling groove 162, provided tosecond body 160's race 161.

Spacer 150 may be joined to inner core 140 by forming projectingportions for being fitted into race 134 and race 161.

Once the above assembly is completed, the antenna cable is inserted intoantenna base 100's through hole to electrically connect the antennacable with connector pin 111, and after antenna base 100 is electricallygrounded, the interval between first body 130 and antenna base 100 isminutely controlled by turning holder 120 while checking the antenna'sperformance. Holder 120 is set by the use of an adhesive agent and thelike at the point where optimum performance is achieved whereby theinterval between first body 130 and antenna base 100, i.e. The overalllength of the antenna is set.

In addition, after the antenna characteristics are controlled byminutely regulating a coupling space between races 134 and 161 of firstand second bodies 130 and 160 via spacer 150, it is fixed by the use ofan adhesive agent.

The space (refer to FIG. 3A) is regulated by using holder 120 in theproduction line, thus minutely controlling the RFC. Finally, the VSWR isadjusted to about 1.0 (refer to table 1).

Accordingly, the RFC is adjusted to about 1.0 the VSWR, as shown intable 1. The smaller the value becomes, the more the antenna performanceis excellent. The antenna's gain of the present invention is greaterthan the other products', as shown in table 1. In table 1 the inventiveantenna is compared to the conventional on-glass antennas A, B and C ingain and VSWR.

TABLE 1 VSWR This A B C Frequen- Inven- Sample Sample Sample SampleSample cy (MHz) tion 1 2 1 2 1 824 3.85 −0.4 −0.2 −0.1 0.1 1.12 836 4.551.6 1.3 0.8 1.2 1.3 848 5.15 0.2 −0.2 0.0 0.3 0.0 869 4.05 0.2 −0.1 −0.6−1.0 0.3 881 4.25 −0.1 −1.2 −2.3 −2.5 −0.5 894 3.45 −0.1 −0.7 −0.2 −0.40.4 average 4.21 −0.1 −0.2 −0.4 −0.4 0.2 824 1.12 1.52 1.36 1.20 1.091.30 836 1.05 1.48 1.42 1.34 1.27 1.54 848 1.05 1.66 1.65 1.46 1.30 1.67869 1.51 1.47 1.57 1.40 1.73 881 1.23 1.37 1.51 1.42 1.62 894 1.07 1.021.40 1.37 1.46 average 1.07 1.41 1.38 1.41 1.31 1.55

The antennas appeared in table 1 are not the same as each other inlength. Each of A, B and C antennas is about 450 to 475 (+/−10)mm, andthe length of the antenna is about 123 mm. The present invention isremarkably shorter than the other products, and assures the excellentgain characteristics and VSWR.

First and second bodies 130 and 160 of the inventive antenna have races134 and 161, respectively, and the antenna's transmitting/receivingfrequency is amplified in the races and inner core andtransmitted/received around spacer 150. Therefore, the overall length ofthe antenna can be reduced.

According to this invention, since each hole is provided to the firstand second bodies to enhance the output characteristics, the length ofthe antenna can be decreased even in a broadband. The depth of each raceprovided to the bodies and the length of the inner core are added to thelength of the outer surface, thus forming the overall length of theantenna. The outer length of antenna base 100, holder 110, first body130, spacer 150 and second body 160 becomes the outer length of theinventive antenna. Therefore, the overall outer length of the antennacan be significantly reduced compared to the conventional antenna'slength.

The structure of the present invention having the races creates thecorresponding RFC between the core and the surface of each race to causephase inversion and RF amplification.

The inventive antenna does not need to be loading-coil one, and itsoverall length is very short to assure low RFR, low radiationresistance, and high efficiency. In addition, since the presentinvention employs the holder system, ANT TOP 101A (refer to table 1) hasbroadband characteristics (806 MHz to 1.87 GHz), and R, CDP, PCS sharedantenna may be used with one antenna.

FIG. 9 is an exploded perspective view of antenna fixing brackets inaccordance with the present invention.

As shown in the drawing, fixing disk 214, corresponding to the bottom ofantenna base 100, has a plurality of screw holes 213 to which screws 211are fastened, and a cable guide hole 212 is formed to receive theantenna cable. A coupling part 216 is formed on one side of fixing disk214 to be curved by a given angle (e.g. right angle) and divided intotwo by an open slit connected to guide hole 212 in such a manner thatfirst and second fixing brackets 210 and 220 are formed. Elastic pieces215 with compressed elastic force are attached to coupling part 216 offirst fixing bracket 210, and second fixing bracket 220's coupling part216 has a coupling slot 216 into which elastic pieces 215 of firstfixing bracket 210 are fitted.

Since first and second fixing brackets 210 and 220 are in pairs, whileone of them is fixed by antenna base 100 and screw 211, the other one isinserted into a certain position within a car (e.g. a gap of a car audioor car air-conditioner). This antenna can be easily installed by joiningthe coupling part of the fixing bracket with antenna base 100 to thecoupling part the bracket this is fixed to the car's interior. Inaddition, since the fixing brackets that are in pairs are notdirectional, they may be joined as indicated by the dotted line of FIG.9.

This preferred embodiment of FIG. 9 is not limited to theabove-described type, and these brackets may be mounted on the outsideof the car. Another type of fixing brackets may be used. Since thefixing brackets are electrically connected with antenna base 100 andserve as an antenna cathode, fixing brackets designed according to thosecharacteristics will do.

The inventive antenna may be mounted in the car, and connector 120within antenna base 100 can be directly coupled to a hands-freeconnector as a pin type. Therefore, hands-free antenna cable connectorcan be directly inserted into the interior of antenna base 100 withoutusing an extra connecting cable.

The conventional antennas cannot not be installed in a car because oftheir big size, and use cables for connection of hands-free connectors,which results in one more connector coupling, and increases the cable'slength. This causes noise and deterioration of performance.

The present invention has the following advantages.

First, the antenna's overall parts can be mechanically (bolt-nut type)assembled by using thee standardized components and the antenna withoutsoldering in the assembly step, thus enhancing the productivity.

Second, the antenna's length can be reduced with respect to thebroadband frequency.

Third, the antenna's VSWR can be set to about 1.0, and its gain ishigher than the conventional one's thereby enhancing the performance.

Fourth, since the antenna for a cellular phone terminal is installed inthe terminal's case, this terminal can be variously designed, andobviates any inconvenience that may occur by the projecting antenna.

It will be apparent to those skilled in the art that variousmodifications and variations can be made in the antenna for mobilecommunications of the present invention without departing from thespirit or scope of the invention. Thus, it is intended that the presentinvention cover the modifications and variations of this inventionprovided they come within the scope of the appended claims and theirequivalents.

What is claimed is:
 1. An antenna for mobile communications comprising: first and second bodies of conductor, each having races whose length and diameter are designed in consideration of the antenna's frequency and gain characteristics; a spacer of a non-conductor interposed between the first and second bodies so as to keep a given space between the respective races of the first and second bodies according to the frequency and gain characteristics; an inner core fixing two bodies to each other with screwed parts respectively inserted into screwed grooves each passing through the races' bottom, and electrically connecting the first body to the second body; and a coupling part for feeder connection of a transmitting/receiving terminal.
 2. An antenna for mobile communications according to claim 1, wherein the coupling part has a bolt portion formed on the first body's protruding lower end, and a female screw joining an antenna connector connected to an antenna feeder of a transmitting/receiving circuit to the bolt portion.
 3. An antenna for mobile communications according to claim 1, wherein, in the coupling part, a pin hole is formed at one end of the inner core and a pin is provided to an antenna connector connected to an antenna feeder of the transmitting/receiving circuit, and the pin hole of the inner core joined to the first body is connected to the antenna connector via a pin for feeding.
 4. An antenna for mobile communications comprising: an antenna anode region including first and second bodies of conductor, each having races whose length and diameter are designed in consideration of the antenna's frequency and gain characteristics; a spacer of a non-conductor interposed between the first and second bodies so as to keep a given space between the respective races of the first and second bodies; an inner core having both ends screwed to each bottom of the races of the first and second bodies to fix two bodies to each other, and electrically connecting the first body to the second body; and a coupling part formed on the first body's lower portion and electrically connecting to a cellular phone's circuit board; and an antenna cathode region formed as the circuit board, corresponding to the, antenna anode region, said antenna being mounted in a cellular phone terminal's case.
 5. An antenna for mobile according to claim 4, wherein the antenna cathode region is designed to be an extra conductive pattern outside of the shield plate.
 6. An antenna for mobile according to claim 4, wherein the antenna cathode region is of the same structure as that of the antenna anode region of which two bodies each having races are spaced a given distance away from each other by a holder and fixed by the inner core, and connected to each other by the coupling part and an antenna connector, said antenna cathode region being installed within the cellular phone terminal's case along with the antenna anode region.
 7. An antenna for mobile according to claim 6, wherein the antenna cathode region makes a right angle to the antenna anode region.
 8. An antenna for mobile according to claim 4, wherein each of the antenna's coupling part and the antenna connector has a pin hole, and said antenna is electrically connected by a pin inserted into each pin hole of the coupling part and the antenna connector.
 9. An antenna comprising: an antenna base having a through hole into which an antenna cable for communications equipment is inserted, and a plurality of screw holes formed on its bottom to mate with fixing brackets; a connector having a bolt portion joined to the through hole's upper section, and a connector pin protruding to the bolt portion's upper and lower parts, a part of the bolt portion being screwed to the through hole of the antenna base, and the antenna cable, inserted into the antenna base, being electrically connected to the connector pin protruding to the lower part; a holder of an insulating material, screwed to the bolt portion of the connector protruding to the upper part of the antenna base, and precisely controlling a minute space between the bolt portion's upper section and an antenna body for regulating the antenna's capacitance; a first body having a bolt portion protruding from its lower portion and joined to the holder, said bolt portion having a pin hole into which a connector pin projecting to the connector's upper part is inserted for electrical connection, and a race of a given depth designed according to the antenna's transmitting/receiving frequency and gain, said race having screwed grooves on its bottom; an inner core having one end screwed to the screwed grooves, and spaced a given distance away from the inner surface of the first body's race; a holder of cylindrical shape having a through hole through which the inner core passes, and formed of an insulating material keeping a space of the first and seconds bodies, designed according to the antenna's transmitting/receiving frequency and gain; and a second body having a race corresponding to the first body's, screwed grooves formed on its inner upper section, for receiving the inner core, and a cap formed on its outer upper section.
 10. An antenna according to claim 9, wherein the holder is fixedly set by an adhesive agent after minutely controlling a space between the first body and the bolt portion of the connector fixed to the antenna base in order to regulate the antenna's capacitance.
 11. An antenna according to claim 9, wherein each of the fixing brackets includes a fixing disk, corresponding to the bottom of the antenna base, having a plurality of screw holes to which screws are fastened, a cable guide hole formed to receive the antenna cable, and a coupling part formed on one side of the fixing disk to be curved by a given angle and divided into two by an open slit connected to the guide hole in such a manner that the first and second fixing brackets, elastic pieces with compressed elastic force being attached to the coupling part of the first fixing bracket, and the second fixing bracket's coupling part having a coupling slot into which the elastic pieces of the first fixing bracket are fitted, so that said brackets are either fixedly inserted into a gap of a car's interior into which the fixing disk can be fitted, or fixedly installed inside or outside of the car by using screws.
 12. An antenna comprising: a first body having a race and a coupling groove at a distal end; a second body having a race and a coupling groove at an opposite distal end; a spacer interposed between the first body and the second body as to maintain a given space between respective races of the first body and the second body according to frequency and gain characteristics of the antenna; and an inner core having respective distal ends fixedly coupled to the respective coupling grooves of the respective races of the first body and the second body as to electrically connect the first body to the second body.
 13. An antenna according to claim 12, further comprising a coupling unit arranged to couple the lower end of the antenna to an antenna feeder of a transmitting/receiving circuit.
 14. An antenna according to claim 13, wherein said coupling unit comprises an antenna connector having a female screw arranged to receive the lower end of the antenna for connection to the antenna feeder of the transmitting/receiving circuit.
 15. An antenna according to claim 13, wherein said coupling unit comprises an antenna connector having a pin hole arranged to couple to the distal end of the inner core, via a pin, for connection to the antenna feeder of the transmitting/receiving circuit.
 16. An antenna according to claim 12, wherein the respective races of the first body and the second body have respective length and diameter designed according to the frequency and gain characteristics of the antenna. 